SS Morro Castle was an American ocean liner that caught fire and ran aground on the morning of September 8, 1934, en route from Havana, then part of the Republic of Cuba, to New York City, United States, with the loss of 137 passengers and crew.

On the previous evening, Morro Castle's captain, Robert Willmott, had died suddenly, and his place was taken by Chief Officer William Warms as a strong northeast wind was developing under heavy cloud. At 2:50am, a fire was detected in a storage locker, which burned through electrical cables, engulfed the ship in flames and plunged it into darkness. Responses by the crew, the United States Coast Guard and rescue vessels were notably slow and inefficient, with lifeboats not loaded to their capacity. The decks were too hot to stand on, smoke made breathing difficult and passengers were forced to leap into ocean swells where swimming was impossible. By mid-afternoon Morro Castle was abandoned and the survivors were landed on the shores of New Jersey by an assortment of craft.

The cause of the fire was never established, though an overheated funnel and certain points of cabin design and electrical circuitry were noted. A theory of arson by a crew member has attracted support over the years, albeit without any concrete evidence. The high casualties are chiefly blamed on the crew's incompetent handling of the emergency.